No difference in efficacy of cancer immunotherapy by sex

medwireNews: Both men and women derive an overall survival (OS) advantage from treatment with immunotherapeutic agents for advanced solid tumors, a meta-analysis shows.

This finding is in contrast to an earlier analysis that showed a sex-specific difference in the efficacy of immune checkpoint inhibitors, with women appearing to benefit less than men.

Advertisement

But the authors point out that the current study expanded the search criteria to include trials of atezolizumab, durvalumab, and avelumab, in addition to those testing ipilimumab, tremelimumab, nivolumab, and pembrolizumab.

And it also included “several comprehensive and updated studies […], including those with a more robust representation of female patients,” that were published since the previous meta-analysis.

The current meta-analysis comprised 23 randomized controlled trials, with a total of 9322 men and 4399 women, comparing immunotherapy – either given alone or alongside chemotherapy – with other systemic therapies, including chemotherapy- and targeted therapy-based regimens, for advanced solid malignancies.

Of note, the analysis excluded three trials that assessed various immunotherapeutic agents and which had been included in the previous study; this allowed the investigators to “specifically assess the association of sex with response to immunotherapy.”.

Advertisement

Compared with the nonimmunotherapy controls, receipt of immunotherapy was associated with a significant OS advantage in both men and women, with respective hazard ratios for death of 0.75 and 0.77.

And a random-effects meta-analysis showed that both sexes derived a comparable OS gain, with no significant between-group differences.

There were also no differences between men and women in terms of response to immunotherapy in any of the analyzed subgroups, including by tumor site, line of therapy, class of immunotherapy, and study methodology.

The OS benefit was also similar for men and women regardless of the proportion of women included in each trial, say Christopher Wallis (University of Toronto, Ontario, Canada) and team in JAMA Oncology.

They point out several limitations of the study, such as the fact that it relies on published hazard ratios and not individual patient-level data, and the potential for residual confounding.

Nevertheless, Wallis et al conclude that “[c]ontrary to findings of a previous analysis, we found no evidence that sex should be considered when deciding whether to offer immunotherapy to patients with advanced cancers.”